Not a lover of Sthil, however the symptoms are lean fuel mixture, check easy stuff first, replace/clean fuel filter in the tank, check fuel hose for cracks or splits,fill tank with fresh fuel, if no faults are found it must be in the carb itself, remove carb and remove the pump side cover from it, here you will find a filter, clean or replace, if you are happy there are no blockages in the fuel system, you can make a small adjustment to the L screw on the carb, 1/2 turn out max ( anti clockwise ) if still no joy this is a job for the dealer
Husqvarna man, December 2009
